If you’re viewing this blog, it seems inconceivable that you do not know what nattō is, but there is nothing wrong with asking the question, and this is where you will find the answer.
Simply put, it is a traditional Japanese food made from soybeans fermented with Bacillus subtilis; however that makes it sound more complicated than it is. What you end up with when consuming the delicacy, are small soybeans with a stringy and slimy texture. The smell and strong taste can also be unpleasant to some. Though it really is an acquired taste.